Carburetor



April 14, 1936.

A} MOORE CARBURETOR File d Feb. 5, 1932 4 Sheets-Sheet 1 INVENTOR Arlznylon Moore 'ATTORNEYfi April 14, "1936. U A. MOORE 2,037,530

I f YCARBURETOR Filed Feb. 5, 1932 4 Sheets-Sheet 2 55 INVENTOR Arlinyion Moore BY: (f 2 Z ATTORNEYS pril 14, 3

MOORE CARBURETOR INVENT I M ore TTORNE Patented Apr. 14, I936 'lTE CARBURETOR Arlington Moore, New York, N. Y., 'assignor, by mesne assignments, to Maxmoor Corporation, New York, N. Y., a corporation of Delaware Application February 5, 1932, Serial No. 591,040

the fuel and air and forming the charge mixture for internal combustion engines, and to methods thereof.

This application is in extension of and. covers advances over my prior copending application, such as Serial No. 525,992 filed March 28, 1931 containing subject matter cognate to that claimed herein. As in said application, I introduce the fuel on that side of the air metering throttle nearest to the engine cylinders. Discharge of the fuel into this region of reduced pressure keeps the fuel from striking against the throttle and materially assists in fuel vaporization. The ample pressure reduction thus made available at the fuel jet eliminates need for depending, during fractional load operation, on constricted venturi air-flow to produce fuel flow, and permits the air conduit to be of ample sec-.

tion, adapted to supply maximum air when the throttle is opened, and allowing the engine to develop its full power without interference by air constriction.

The pressure reduction about the fuel jet, so located however, increases as the throttle is adjusted towards closed position, while the fuel requirements decrease.

In the form of the invention herein disclosed, as in that of said application Serial No. 525,992, I control the fuel supply to accord with the air supply, notwithstanding that the intake depression inductive effect on the fuel tends, when the air is manually varied, to vary in inverse relation to fuel requirements.

This control of the-fuel is in part accomplished by maintaining the pressure difference on the fuel less than that in the intake by introducing primary air into the fuel passage at the discharge side of the fuel'metering orifice, which air introduction is termed herein as air bleeding, thereby enabling the use of fuel metering orifices having areas larger than would be required to pass the proper fuel in response to the full intake depression, and avoiding excessively small fuel pas- -sage areas productive of high coeflicients of friction. I also control the fuel flow by variation of the fuel metering orifice area with changes in air passage area together with making compensation for intake depression changes due to speed change. Thus the required fuel is supplied for a given load or speed condition at each throttle position partly by regulation of fuel passage area and partly by regulation of pressure differential effective to produce fuel flow as the speed varies at each throttle position.

Atv full load operation, when the intake depression is low and the fuel requirements high, I also utilize,'as in the invention disclosed in said application 525,992 air flow by venturi effect for augmenting fuel flow, the venturi effect being 5 negligible at fractional load operation. The pressure difference effective for fuel flow is thus augmented by venturi effect at full load operation while the effect of intake depression on fuel flow is substantially reduced by air bleeding effeet at fractional load operation.

Bleeding air with the fuel, particularly when, as in the present invention, the fuel is discharged into the region of reduced pressure, also facilitates the atomization and vaporization of the fuel, and facilitates the fuel lifting when the pressure differentials are low.

The carburetor of the present invention also comprises means similar to those disclosed in the above mentioned application for supplying fuel in uniform quantity at engine idling and for supplying additional fuel upon engine acceleration.

An object of the present invention is to provide a device of the character specified which is simple and compact in construction, capable of being produced at low cost, and efficient in operation.

Another object of the invention is to prevent attenuation of the pressure differential on the fuel metering orifice by primary air introduction under load conditions characterized by low depressions so as to obtain adequate fuel under such conditions of engine operation.

Another object of the invention is to effect'variation of the fuel metering orifice without development of coefiicients of friction causing erratic fuel flow.

Other objects of the invention are to effect 40 metering of the fuel from the air valve without causing back lash, distortion and the like, whereby to obtain precision in metering; to effect uniform metering of fuel at engine idling productive Fig. "4 is a sectional elevation thereof;

geneous mixture with'the air.

Influence of air flow on fuel flow I utilize the air flow for producing depression, augmenting intake depression when the same is weak, to vary the fuel flow directly with the air flow to such extent as can be done without constricting the air flow, by locating thefuel nozzle ill in one portion of the angular passageway I 2 in the casting l4 on the side of the air metering throttle I6 toward the engine cylinders and preferably at the throat of a venturi I8, the throttle being located in the entrance portion of conduit l2 so that the air is deflected to obviate air stratification at certain throttle positions prior to admixture with the fuel. The air flow through venturi 18 serves to produce depression of useful magnitude at full load for promoting fuel delivery. Venturi l8 also assists the elbow bend in conduit I2 I in rendering the air uniform in density.

Fuel blasting and vaporizing I blast or comminute the fuel bygaseous fluid, such as air preferably supplied at atmospheric pressure and induced'by the pressure reduction in the intake, this arrangement being satisfactory for lighter fuels, such as gasoline. The air is discharged through the central tubular nozzle 20 and the fuel supplied therearound'through the annular passage 22 between air nozzle 20 and the fuel nozzle l6.

The nozzles l0 and 20 are secured within a bore 24 of the casting l4, the casting being provided with a fuel passage 26 terminating at the bore 24. The nozzle 20 has a relatively restricted metering orifice 28 for regulating the quantity of air admitted for effecting the desired atomization of fuel. The nozzle i0 has a relatively long cylindrical end portion 30 projecting beyond the discharge end of the air nozzle 29, the length of said projecting portion exceeding several times the diameter of the nozzle ID. The fuel aerated as hereinafter described and discharged into the passage or chamber 30 is subjected to the comminuting action of the air from nozzle 20, which obtains a high degree of atomization because of the elongated passage 30, without appreciable change in the normal fuel lifting effect available. The fuel is thus subject to an aerating action, air blast, and pressure reduction in the intake for effecting fuel atomization and vaporization so that the fuel rapidly permeates the air entering through opening 32 and forms a homo- The vaporizing effect can be augmented, if so desired by application of heat.

While I have illustrated a carburetor of the up-draft type, the invention is also applicable l4 to which the float chamber bowl is secured. The casting l4 comprises a depending portion 36 extending into the fuel in chamber 34.

The portion 36 is provided with a vertical bore 38 terminating in passage 12 below the air throttle l6. A sleeve 40 having a fuel metering orifice 42 below the fuel level is disposed within the bore 38. Fuel is supplied from bowl 34 past check valve 44 and through lower portion of accelerating well 46 and passage 48 to the fuel metering orifice 42, and, after being metered by valve 50, passes'through a vertical passage 52 into passage 26.

The valve 50 having a shape as hereinafter described is adjustable in metering orifice 42 and isactuated from the air throttle IS, the valve having a tapered head 54 coacting with the contoured edge of the cam 56 which comprises a vertically disposed plate secured directly to and centrally of the throttle plate l6 within the passage I2. I

The valve 50 is maintained in engagement with the edge of cam 56 by a spring 58 interposed between sleeve 40 and abutment 60 on the valve stem. o

The cam plate 56 is also provided with an ear 62 to which the piston 64 working in well 46 is pivotally connected through stem 66, said stem including a flexible shaft portion 68 so that the plunger or piston 64 can be actuated by the throttle without binding of the parts. The well 46 above piston 64 is vented to atmosphere by opening 10 into the bowl 34 above the fuel level therein. v

I so arrange the edge contour 12 of cam 56 so as to take care of changes in intake depression due to air throttling being substantially inversely related to need for fuel.

' I overcome this inversion and obtain fuel flow to accord with air flow by causing the cam-controlled fuel' valve 50 to give an opening 42 for each air.-throttle opening of a sizeto pass the needed fuel in response to the depression effective on the fuel orifice which, as will be seen later, I keep less than the depression in the venturi at the fuel nozzle, except at low speed full load operation. I preferably obtain the predetermined openings of the fuel oriflce by providing cam 56 for operating fuel valve 50 with an edge contour 12 having a predetermined configuration productive of the proper fuel flow, which will be referred to in further detail hereafter. I take care of the fuel needs changing with engine speeds for each fuel valve position by suitable variation of the pressure differential acting on the fuel, as hereafter described under another heading.

While the fuel valve 50 can be arranged to supply fuel for idling, I prefer to handle the idling fuel separately in manner described below, and bring the main fuel valve 50 to a substantially closed position during engine idling, thereby avoiding adjustment of the fuel valve 50 for regulation of idling fuel.

Calibration The internal combustion engine, such as employed for example in motor vehicles is controlled by means of the throttle to compensate for load or to vary the speed. At each throttle position the speed varies inversely with the load, the maximum speed becoming greater as the throttle opening increases. The fuel required for operation at minimum speeds varies, in general,

directly with the throttle opening. It also varies directly with the speed at each throttle position. For economical operation the mixture ratio is varied as the conditions of operation vary, the mixture being made richer for certain conditions of operation and leaner for other conditions of operation. In my invention I control or adjust, as hereinafter described, the pressure differential range effective-for causing fuel flow at the various throttle positions, and then produce for each throttle position through cam 56 the particular fuel passage area individually determined for allowing under the adjusted pressure differential as the speed varies, a fuel flow in suitable ratio to the air supplied.

To determine the contours 12 of a key or cam 56, so as to properly control the opening of fuel valve 50 for any particular type of engine, I operate an engine representative of such type at various fixed throttle openings under various loads productive of various speeds. I then'adjust valve 59 for each of the several throttle openings until'desirably good operation is obtained under such conditions, and form the cam edge-12 so that, when it is put in place in the apparatus, the test openings of valve 58 are duplicated for the several throttle positions. In this way a predetermined correct opening of fuel valve 50 is obtained to go with each air throttle position.

The typical cam contour formation so obtained as shown at Fig. 8 is substantially continuous, the parts merging into one another, and having the points thereof located to give the fuel passage opening corresponding to the differing conditions for various throttle positions, The part 14 of the cam edge 12 engaging the end 54 of valve 58 during engine idling when the air throttle I2 is substantially closed, may bereferred to as substantially neutral, being adapted to hold valve 50 so that practically no fuel is passed. The fuel supply for idling is obtained through a special idling jet l6 hereinafter described and sufficient air for slow engine idling is admitted through the several air bleed apertures, the nozzle 28, and the small balanced idling air holes 18 in the air throttle 16.

The cam part functioning for example at small throttle openings is the part coacting with and determining the opening of valve 58 during very low fractionaHoad operation at which time fuel through idling orifice I6 is being supplied. This in motor vehicle engines represents the takeout period of merging from idlingifito power operation, and the movement of fuel passage opening for movement of throttleopening is least.

Another cam part functioning for-example at the wider throttle openings increases the fuel valve opening at more rapid rate after the idling orifice I6 ceases supplying any material part of the fuel and the intake depression starts decreasing with throttle opening.

The calibration determination of the cam contour is made with the air bleed 82 opento decrease the pressure difference on the fuel orifice 42 as. hereinafter described. The calibration is also made under other conditions of engine operation such as with-the air nozzle 28 and the idling f el jet 16 in operationto supply air. The calibr tion being made under such conditions, in actual operation of the engine, proper |fuel-toair ratios may be obtained for maximum torque, maximum horse power and maximum economy, each independent of the other. By making the calibration of the fuel passage areas for certain speeds, such as a low speed at each throttle position, proper fuel for such speeds is insured,

and each fuel passage opening is suitable with the changed pressure difference on the fuel to supply proper fuel at other speeds.

Air bleed to fuel conduit To suitably vary the fuel flow upon speed changes at each throttle position and the cor-.

responding fuelvalve position, and to lessen the high depfessiofi at the exit side of the fuel valve port 42, the vertical passage 82 is provided for limited communication from a source of air at atmospheric pressure to the fuel conduit at a point 84 immediately beyond the orifice 42 but still below the fuel level. The upper end of the passage 82 terminates in a metering orifice 86 of predetermined size located within the float,

chamber 34 above the fuel level and receiving air from within the float chamber.

the fuel gate 42 bythe admission of air through "the bleed passage 82 enables the use at periods of high intake depression of a fuel passage opening at 42 larger than the small opening that would have to be used to hold the fuel back against the full intake depression, with resulting elimination of the irregularity of flow that would be incidental to use of such smaller opening and greater depression.

The variations in intake depression effective on the fixed' air bleed hole 84 give a sufficient corresponding variation in air flow therethrough and in fuel flow through valve port 42, in response to the remaining depression effective to produce fuel flow, to keep the fuel-to-air ratio from going up unduly with increase in engine speed for each air gate andfuel gate position, the air bleeding effect increasing with increase of depression upon increase in speed at each throttle postion.

At wide open air-throttle operation, for example. when the fuel gate position at 42 is fixed by fuel valve 58 at the maximum opening, the induc-- tive effects on the fuel of intake depression and air fiovi vary directly with the speed and so di-- rectly with need for fuel, the air bleed ng effect then be ng minimum, and the resultant pressure difference enables the securing through the unchan ing fuel passage opening, of the variation of several hundred percent in fuel fi'ow that is required through the speed range in full load op--' 'e a ion.

The admission of air at 84 w th the metered fuel coming in at 42 produces an air-fuel mixture in the conduit which. on passing to nozzle Lis more effectively broken up than solid liquid fuel by blast ng and/or delivery into partial vaci um. As the fuel has already beenmetered at 42 prior to admixture with the bleeding air, the correct air-to-fuelpreportioning can be obtained. i

While the depression available with my process a could be 'used to lift fuel hrough some distance, I d spense with such functicn, and supply the fuel cl se up to'the nozzle at a constant floatcom' tro led level, to avoid the irregularities in supply of fuel that occur when fuel is lifted through substantial distances.

Q able frictional retardation, the action being acis ,materially reduced by the communication passage 82 is submerged below the fuellevel in the float chamber so that, when the pressure in the intake is atmospheric, fuel will rise in said passage 82 up to the level of the fuel in the float chamber. It follows therefore that, upon engine operation, the reduction in pressure in the intake must attain a value suflicient to draw the fuel out .of or dump the passage 82 before the primary air becomes effective in reducing or attenuating the pressure reduction at the metering orifice 42.

Should the depression during engine operation,

such as at low speeds characterizing engine lugging conditions, fall below that required to dump the passage 82, the latter hydrostatically fills with fuel to automatically close off the introduction of primary air, and thus to render the entire avail able pressure reduction in the intake or venturi effective in producing fuel flow. The critical 20.

value of depression at which the passage 82 dumps the fuel or fills with fuel depends on the extent of submergence of said passage and of the metering orifice 42, the extent of submergence being designed in each case to satisfy the requirements 'for operation: The hydrostatic control of the primary air as above described provides effective means for tailing up the mixture ratio at low speeds characterizing engine lugging conditions, and thereby reduces the liability of the engine-stalling at such low speeds.

At engine idling air passage 82 is open and fuel valve port 42 is substantially closed so that the fuel conduit 52 admits air only, and such air serves as a carrier for the idling fuel mixture supplied at 16 and delivered to the fuel nozzle l0 through the last reach 26 of conduit 52. Furthermore, the depression for supplying idling fuel through passage 82 to atmosphere being open.

I have found in modulating the fuel flow in some types of engines through a metering orifice employing the well known tapered or conical metering pin,.formin.g an' annular orifice, ,that the fuel flow at certain light engine loads is erratic, the fuel flow tending to lean out or fall off. I have discovered that this decrease in fuel flow is due to frictional coefficients inherent in the use of a variable annular orifice for fuel metering subject to high pressure differences.

When metering fuel with an annular orifice,

. say at 10 of throttle opening, even when employing air bleeding, the clearance must be of the order of .00125 so as to prevent excessive fuel flow at the high intake depression existing at such throttle position. An annular orifice of such size is so small that light'hardly passes through the same. Fuel passing through such highly restricted orifice is therefore subjected to considercumulative and gradually reducing fuel flow. That the" disturbing effect of the coefficients of friction is serious with an annular orifice is evidenced by the fact that the fuel flow has been 2,087,530 .It will be noted that the ve'rtical primary air 42 having a cross-section which is lumped or concentrated, approximating in shape a round hole insteadof an annulus so. that the wall;surface of the orifice frictionally retarding the fuel flow is minimum and the minimum dimension thereof is substantially greater than the minimum dimension of an annular orifice.

In order to form the variable lumped orifice 42, the lower end 88 of the valve 50 is made cylindrical with one side thereof cut or slabbed off at an angle, as indicated at 90, to form a frustrum. The angle of the plane cut 90 is such as to allow variation in the area of the fuel orifice throughout the relatively smallrange of movement of the pin 5D, and is so coordinated with the cam contour 12 that an orifice of the desired fuel passage area is obtained at each throttle position.

In the position of the valve 50 shown in the -drawings the completely cylindrical portion of the pin 50 substantially closes the orifice 42 to preclude the passage of fuel therethrough at engine idling. As the valve 50 moves withopening movement of the throttle the fuel passage area at 42 increases, the orifices of increasing area The lower valve portion 88 is preferably separate from the upper portion 94, and is preferably loosely received into a socket 96 in portion 94 and inovably retained therein by a pin 98. This allows the portion 88 to line up with the orifice 42 should the same be made slightly off center in manufacturing.

The frustrum type of metering valve may be more readily manufactured and installed than the conical type of valve, a erance being allowable.

As shown at Fig. 11 the valve '50 may be made with a cut 9i! having a predetermined contour or curve, instead of being made plane as indicated at 90, Fig. 10. With this arrangement the pin 50 can be connected to the throttle for movement directly therewith without the use of the interposed cam 56. In such case the cut contour 90 is formed to give at each throttle, position a segmental metering orifice of 'the area desired for that throttle position. l

The provision of means for varying the fuel passage area 42 in the manner above described.

in conjunction with air bleeding into the fuel at 86 not only insures steadiness in fuel flow under constant conditions of engine operation but also allows greater precision in air bleed adjustment at 86 for controlling the differential pressure on the orifice 42 for engine load variations, making it possible to obtain a substantial increase in economy.

With my carburetor the mixture ratio can be adjusted or altered at service stations or elsewhere merely by replacement or substitution of the air bleed jet 86 which is removable. For example, with a cam 56 of predetermined contour and a metering valve 50 of a predetermined cut at 90, the mixture ratio for the entire range of engine operation can be made" leaner by use of a largerair bleed and richer by use of a smaller air bleed, the correction being made for the entire range of engine operation substantially equally effectively for all stages of engine operation so that it is impossible, although the adjustment is simple, to obtain faulty operation at any stage of engine operation, the adjustment when made being satisfactory for the entire range.

The frustrum type of metering valve while engreater range of 1301- abling precision in fuel metering also enables production at low cost, and the same, when carburetor cost is a factor can be advantageously utilized for controlling the fuel orifice 42 to sup ply fuel for engine idling as well as at other stages of engine operation, the relatively low coefficients of frictions characteristic of the lumped type 01 metering orifice being productive of steadier fuel flow at engine idling. I prefer however, where cost is not material, to utilize for supplying idling fuel the means 16 hereinafter described, because such means is substantially immune to fluctuations in intake depression at angine idling.

Regulation of fuel flow for various engine speeds If the engine speed is increased with the air metering throttle wide open, the air flow increases :rapidly, necessitating a correspondingly considerable increase in fuel supply. A typical case is increase from 100 .00. per min. at substantially minimum speed to 500 cc. per min. at substantially maximum engine speed, both at wide open throttle. As has been seen, the fuel passage area is maximum when the throttle is wide open. Venturi I8 is chosen of such throat size that the depression on the fuel nozzle I located at the throat thereof rises in response to air flow increase resulting from engine-speed increase at wide open throttle so as to cause the required fuel to pass through the wide open fuel conduit, and at this time the air bleeding effect is least because the pressure differential on the passage 82 -is least. 1

As the venturi is not relied on to induce fuel fiow at low fractional loads, as is the case with ordinary carburetor practice it can serve the function of promoting fuel fiow at and toward wide open position of the air throttle, and still be large enough not to cause restriction of air flow and reduction of charge density.

If the throttle be closed somewhat from wide open position, as, for'instance, to 50, while this makes substantially no difference in air flow and fuel fiow at low engine speeds,-there is a material reduction in air fiow at the higher speeds, with resulting reduction in need for fuel. At such times, however, the intake depression-is higher, but the air bleed passage 82 is more effective in reducing the pressure reduction across fuel valve seat 42, the fuel flow being correspondingly decreased, and the requirements for economical operation satisfied. Upon passing to-the lower part fractional load operation, the intake depression is further increased by the further closing of the throttle and the fuel passage area correspondingly reduced in consonance with reduction of throttle opening, and this automatic air-bleed compensation becomes increasingly effective.

It will be seen that by my invention at the higher intake depressions, for example, at in-.

take depressions above that existing at wide open throttle high speed, I reduce the effects thereof on fuel fiow by air bleeding, and at the lower intake depressions augment the fuel flow inducing effects by airflow through a venturi. The pressure differential on the fuel is thus kept within range to cause, upon fuel passage area adjustment, a fiow of fuel in suitable ratio to the air throughout the speed range at each of the throttle positions. At partly open throttle positions the air bleed is'moreeffective for reducing the pressure differential on the fuel throughout. the speed range at each of such throttle openings, the airbleeding efiect increasing with speed increase and consequent'intake depression increase, more rapidly than the fuel flow increases. For maximum throttle opening the air bleeding orifice 86 is adjusted in area to cause economical fuel flow at maximum speeds, 5

neutralizing the tendency of the venturi at such high speeds to cause excessive fuel flow. At minimum speed full load, as above described, the primary air passage 82 closes to render the.

entire available pressure reduction effective for m inducing fuel flow.

Fuel for idling I preferably supply the fuel for idling entirely independently of the main fuel supplied at other stages of operation, i. e. without being affected by variations in fiow of main fuel, and at a relatively constant minimum rate notwithstanding variations or fluctuations of intake depression at or near idling operation. To obtain such result I lift fuel in a solid liquid state through duct I00 from the constant level float chamber 34 into a horizontal chamber or passage section I02 having a relatively weak pressure reduction therein obtained by venting one end of the chamber below the top thereof to the intake through the highly constricted orifice l6 and by venting the other-end of the chamber I02 at substantially the same level to the atmosphere through orifice I04 opening into the top of the bowl 30. The

pressure reduction developed in chamber I02 attains a value, which is relatively constant, sufficient to lift the fuel into the chamber at the high intake depressions prevailing at or near idling operation so that the idling fuel is available at such stage of operation.

The fuel thus lifted forms a fuel level in chamber I02 without entirely filling the same, thereby preventing vapor locking, which is subjected to the turbulent effect of the air passing through orifice I04, and sweeping over the fuel or therethrough to form, apparently, a compressible suspension of fuel in air. The resulting suspension or mixture is squeezed through the highly constricted orifice 16 for delivery through passage 48 52 and 26 into the intake beyond the throttle. The fixed orifice 16 serves to meter the fuel component therethrough at a substantially constant rate, the mixture being wire drawn, in effect, and issuing through the orifice I6 as a fine stream of atomized fuel particles.

Air bleed opening I04 is preferably somewhat larger than the metering jet opening 16, as, for example in one type of engine the opening I6 was .014" in diameter and opening I04 was .022" in diameter. Satisfactory operation has been, obtained with air bleed opening I04 of the order of .020" to .024" in diameter and with a metering orifice 16 of the order of .013" to .015" in diameter.

As already stated, the air bleed passage 82 is open to-the atmosphere during idling so that the depression on the metering idling jet 16 which discharges into passage 52 is less than the depression at the fuel nozzle I0, thus enabling the 804 of about the sizes above named I find that the idling fuel flow remains substantially constant, giving very smooth and steady idling "that does not surge materially even with considerable fluctuation in intake depression.

The idling fuel passage I00 and orifices I6 and I04 remain open at all times, but, inasmuch as the idling jet 16 is above the fuel level, and chamber I02 is vented at I04, the fuel quantity supplied at I6 is substantially negligible except at idling and during blending into low fractional load operation, the idling fuel supplied being sufficient to wet the manifold to facilitate passage of the engine from idling into load or speed operation. The contour of the cam edge I2 for controlling the first opening of valve is such as to supply at 42 only the fuel required in addition to-that already available at 16, so that there is secured from idling a smooth transition or take-cu into fractional load operation.

In order to prevent the chamber I02 from flooding and causing flow of solid liquid fuel into the passage 52, the lower end of the passage I00 is provided with a relatively restricted metering orifice I 66 which chokes off the fuel flow sufiiciently to maintain a fuel level in the chamber I02 which under all conditions of engine idling operation remains below the air bleed opening I04, this being conducive to the supplying of fuel more uniformly at engine idling. With the orifices I6 and I04 of about the diameters of the order above described, a satisfactory diameter for the orifice I06 has been found to be about .020". I

If the air bleed orifice I04 were located above the center of the fuel exit orifice I6, the amount of fuel discharged through I6 would be greater, and if the same were located below orifice I6 fuel flow through I6 would be less. Therefore, to effect consistent fuel control, it is necessary to have the idling air bleed I04 on a center line of the exit orifice 16. Without the use of the constricted metering orifice I06, at times erratic fuel metering would occur, as for example, if the engine is accelerating and the throttle is suddenly closed immediately thereafter, the resulting high depression would cause chamber I02 to fiood above its normal level, producing a short circuit of the air bleed I04, causing an" unduly rich idling condition. With the use of orifice I06 it is possible to maintain a consistent, uniform idle under conditions for good engine operation, the metering orifice I06 preventing,

because of its limited capacity to allow fuel flowtherethrough, sudden changes in fuel level in the idling chamber. I

In the present-invention the bleed openings 86 and I04 are vented to atmosphere within the fioat chamber 34 itself which in turn is vented to the atmosphere through an opening I 08 through a saddle portion IIO forming a continuation of the intake air passage i2. portion H0 is adapted to support an air cleaner II2, preferably'combined with sound deadening means, which is secured in place by means of the band H4 and bolts H6. The air supplied through opening I08 is thus thoroughly filtered to prevent dust and dirt from clogging up the restricted air bleed orifices.

The air throttle I6 is actuated by the compound leverage system II8, shown at Figs. 3, 5, and 6, adapted for plural actuation from the drivers seat in a well known manner.

The fuel pump 64 is used as an effective means The' fuel flow which occurs when the throttle is thusopened to increase the speed and the intake depresslon falls momentarily to practically atmospheric pressure. This prevents momentary hesitation of the engine.

In the present invention, I dispense with interconnecting mechanisms for the control of the movement of the metering pin 50, thereby preventing back lash, distortion and thelike, detrimental to precise metering.

By my invention, the pressure differential on the fuel and the fuel orifice variation are 00-- ordinated so that the fuel is supplied smoothly in suitable ratio to the air substantially throughout the range of operation of the engine without being impeded by frictional effect-s, notwithstanding that the. intake depression variesat times in inverse relation to the fuel requirements, and at other times, while varying directly with fuel requirements,-tends to' cause either too much fuel fiow or not enough.- With my system of fuel control the pressure reduction beyond the throttle is made available for the discharge of the fuel directly thereinto so that the fuel, by discharge into a region of reduced pressure, is more easily vaporized, and the same may be discharged directly into contact with heated surfaces without being impeded by the throttle. Fuel atomization and vaporization are also assisted by the bleeding action and by discharge of air centrally through the annular stream of emulsified fuel, so that the fuel assumes under the action of the several vaporizing influences, a thoroughly homogeneous state in suspension in k the air.

Having thus described my invention, what I claim and desire to secure by Letters Patent is:

1. In apparatus for supplying and proportioning charges for internal combustion engines comprising a member having an intake passage, and including a depending portion having a fuel passage into the intake passage, a float chamber disposed about and receiving said depending portion, a throttle having a cam portion in said Q intake passage above said depending portion, and a valvular member in said dependinglportwn for controlling the fuel passage and terminating in said intake passage in engagement with said cam portion to be actuated thereby.

2. In apparatus for supplying and proportioning charges for internal combustion engines comprising a member having an intake passage and including a. depending portion having a fuel passage and an accelerating well into the intake passage, a float chamber disposed about and receiving. said depending portion, a throttle disposed within said intake passage above said depending portion and including a portion having a cam edge of predetermined contour, a valve for controlling the fuel flow having a bearing in said depending portion and projecting above said depending portion to engage said cam edge, and a plunger working in said, well and having a stem portion projecting above said depending portion and connected to said cam portion.

3. In apparatus for supplying and proportioning charges for internal combustion engines comprising an intake, an air controlling means for controlling the air supply to regulate the development of power through the various parts of engine operation, said means carrying a cam having a contour corresponding to a predetermined fuel curve, means including a metering orifice for conducting fuel into the intake at the engine side of said air controlling means, means for in- I troducing primary air into the fuel conducting means at the discharge side of said metering orifice to modify the pressure difference on the orifice relative to the intake depression available, and valvular fuel controlling means having an end thereof engaging said cam and actuated thereby to give at each air control position an orifice area co-ordinated ,with said means for introducing primary air for allowing a fuel flow, in response to the adjusted pressure differential effective thereon, which is in suitable ratio to the air supplied substantially throughout the pressure differential range.

4. The herein described process of supplying charges for internal combustion engines and proportioning the air and fuel, comprising controlling the passage of air to the engine cylinders for regulating the power production throughout the range of engine operation, introducing fuel through a metering orifice into the air at the engine side of the air controlling means subject to the pressure reduction at the point of fuel introduction while introducing primary air into the fuel line over said metering orifice for reducing the pressure differential thereon, and controlling the metering orifice to produce at each orifice control position a metering orifice of concentrated area coordinated with the attenuated pressure differential on the orifice to reduce frictional coefficients while allowing a fuel flow in suitable ratio to the air.

5. The hereindescribed process of supplying charges for internal combustion engines and proportioning the airand fuel, comprising controlling the passage of air to the engine cylinders for regulating the power production throughout the range of engine operation, conducting fuel through a metering orifice into the air at the engine side of the air control in the region of intake depression while introducing air into the fuel over said metering orifice for reducing the pressure differential thereon, and producing for each of the air control positions a metering orifice of concentrated area coordinated with the reduced pressure differential on the orifice to reduce frictional coefficients while allowing a fuel flow, in response to the pressure differential on the orifice, in suitable ratio to the air supplied.

6. In apparatus for supplying and proportioning charges for internal combustion engines comprising an intake conduit, air controlling means therein for regulating the power production throughout the range of engine operation, means for supplying fuel to the intake conduit at the engine side of the air controlling means, including a metering orifice, means for introducing air into the fuel supplying means at the discharge side of said metering orifice to reduce the pressure differential thereon, and a valve operated automatically and coacting with said metering orifice to form a concentrated orifice opening, the concentrated orifice area and the reduced pressure difierential on the orifice at each valve position being coordinated to minimize orifice frictional coemcients while allowing fuel flow in suitable ratio to the air supplied.

'7. In ,apparatus for supplying and proportioning charges for internal combustion engines comprising an intake conduit, an. air throttle therein for regulating the power production throughout the range of engine operation, means for supplying fuel to the intake conduit at the engine side of the throttle, includinga metering orifice, means for introducing air into the fuel supplying means at the discharge side of said metering orifice to reduce the pressure differential thereon,

ing charges for internal combustion engines comprising an intake conduit, an air throttle therein for regulating the power production throughout the range of engine operation, means including a float chamber for supplying fuel to the intake conduit at the engine side of the air controlling means, and including a submerged metering orifice, means for introducing air into the fuel supplying means below the fuel level at the discharge side of said metering orifice to reduce the pressure differential thereon, and a valve operated by the throttle in accordance with a predetermined fuel curve and coasting with said metering orifice to form a concentrated orifice opening, the concentrated orifice area and the reduced pressure differential on the orifice being coordinated at each throttle position to reduce orifice frictional coefficients and cause a fuel flow in suitable ratio to the air supplied.

9. In apparatus for supplying and proportioning charges for internal combustion engines, comprising an intake, a pivoted throttle therein for regulating the power production throughout the range of engine, operation, means for supplying fuel into the intake at the engine side of the throttle including a metering orifice, means for i introducing primary air into the fuel supplying means at the discharge side of said orifice to reduce the pressure difference thereon, a member attached to said throttle for pivotal movement therewith and having a cam edge of a predetermined contour, and a spring controlled valve coacting at one end with said orifice and retained at the other end by said spring in engagement with said cam edge, said valve'being actuated by said cam edge to provide an orifice area at each throttle position coordinated with the attenuated pressure difference thereon to produce the desired fuel flow.

10. In apparatus for supplying and proportioning charges for internal combustion engines comprising an intake including an entrance passage portion having a depending part, a pivoted throttle in said entrance passage portion for regulating the power production throughout the range of engine operation, a fioat chamber receiving said depending part, means including a metering orifice in said depending part for conducting fuel into the intake at the engine side of the throttle, means in said depending part for introducing air into said fuel conducting means at the discharge side of said metering orifice for curve, and a sprim controlled valve slidably dis posed in said depending part for controlling said metering orifice, and retained at one end by said spring in engagement with said cam edge to be moved thereby.

11. In apparatus for supplying and proportioning charges. for internal combustion engines comprising an intake having an entrance passage portion, a throttle, pivotally mounted in said entrance portion, a part at the exterior of said entrance portion having a fuel passage therein communicating with the intake at the engine side of the throttle, and including a metering orifice having the axis thereof substantially aligned with the pivot of said throttle, said exterior part havfuel flow in accordance with a predetermined fuel curve, the coordination being such as to minimize orifice frictional coefllcients.

12. In apparatus for supplying and proportioning charges for internal combustion engines comprising an intake having a horizontal entrance portion, a throttle pivotally mounted in said entrance portion, a depending part at the exterior of said entrance portion having a fuel passage therein communicating with the intake at the engine side of the throttle, and including a metering orifice having the axis thereof substantially aligned with the pivot of said throttle, said depending part having a passage therein for introducing primary air into the fuel passage at the discharge side of said metering orifice to reduce the pressure difference thereon, a float chamber receiving said depending part and submerging sa d metering orifice, a spring controlled valve slidably disposed in said depending part for controlling the area of said metering orifice, and a member attached to said throttle for pivotal movement therewith and having a cam edge riding on the inner end of said valve to move the same against the tension of said spring, said cam edge having a contour coordinating the area of the orifice at each throttle position with the attenuated pressure difference on the orifice to produce a fuel flow in suitable ratio to the air supplied, the coordination being such as to minimize orifice frictional ooeffioients.

13. In apparatus for supplying and proportioning charges for internal combustion engines com-- prising a member having an intake passage and including a depending portion having a fuel pac sage and an accelerating well therein for supply ing fuel to the intake pas ge, a float chenber disposed about said clepe' ng portion, ti pivotally disposed in said in said depending portion, a n sad throttle for pivotal more having a cam edge oi pr valve member slidably dis' s portion for controlling tli tained at one end/in cage edge, and a plunger in s" projecting above said donates acting with said cam member to be actuated thereby.

sure differential effective/in producing fuel flow,

.15. Process in accordance with claim 14 in which there is produced for each throttle position a predetermined orifice area coordinated with the pressure differential efiective thereon to give a desired fuel flow at various speeds.

,16. Process in accordance with claim 14 in which the fuel orifice is submerged in a constant level source of fuel supply.

1'7. Process of supplying charges for internal combustion'engines, comprising controlling the main air supply to regulate the power output throughout the range of engine operation, delivering primary air into the intake at the engine side of the point of main air control together with fuel introduced into the primary air through a submerged metering orifice subject to an attenu atcd variable pressure differential produced by the introduction of primary air over the metering orifice, producing for each throttle position a predetermined orifice area to supply the fuel in suitable ratio to the air, the attenuation in pressure differential produced by the primary air being made to approach a maximum to allow the use of metering orifice areas having frictional coemcients approaching the and at low depressions closing off the primary air by the fuel hydrostatically to effect fuel delivery through the metering orifice under a greater pressure differential.

18. In apparatus for supplying and proportioning charges for internal combustion engines comprising an intake having a throttle therein for regulating the power production throughout the range of engine operation, a passage for conducting primary air into the intake at the engine side of the throttle by the action of the intake depression, a fioat chamber having a fuel metering orifice therefrom into the primary air passage, said metering orifice and the inlet to said primary air passage being coordinated in area to control the fuel flow so as to compensate for intake depression, said float chamber and said primary air passage being so related that the fuel closes ofi the supply of primary air at low depression in the intake.

- iii. In apparatus for supplying and proportioning charges for internal combustion engines coinprising an intake having an air throttle therein for regulating the power production throughout the range of engine operation, and a passage for conducting primary air into said intake at the en glue side of said throttle by the action of intake depression, a float chamber having a submerged. metering orifice therefrom to the primary air passage, said metering orifice and the inlet to said primary air passage being coordi 'ed in area compensate for the intake depre in at various throttle pcsitions, said passage l ydrostatioally leading with fuel at low depression closing off the primary air, and means djunciively 21. In apparatus for supplying and proportionto throttling for producing a metering orifice of predetermined area.

20. In apparatus for supplying and proportioning charges for internal combustion engines comprising an intake, a throttle therein for regulating the power production throughout the range of engine operation, a float chamber, means partially submerged in the float chamber fuel for conducting primary air into the intake at the engine side of the throttle subject to the intake depression substantially over the range thereof, said submerged portion fllling with fuel to close oi! the primary air at low depression, a fuel metering orifice opening into the submerged portion of said primary air conducting means,- and having a variable pressure differential thereon attenuated by the primary air, cam means operated adjunctively to throttling for producing at various throttle positions metering orifice areas coordinated with the pressure diiferential eflective on the orifice for producing desired mixture ratios, said orifice areas being proportional to the amount of primary air admitted for reducing frictional coeflicients in the orifice.

ing charges for internal combustion engines comprising an intake, a throttle therein for regulating the power production throughout the range ofengine operation, a venturi in the intake at the engine side of the throttle, a float chamber, means including a submerged metering orifice for conducting fuel into. the intake at a point subject to the fuel flow inducing effect of said venturi and intake depression, means for introducing primary air over said metering orifice to reduce the pressure diflerential thereon, said last named means being controlled hydrostatically by the fuel to close OK the primary air at low depression, and attenuating the venturi eifect on fuel flow at high speeds, and cam means operated by the throttle for producing at each throttle position a fuel orifice area coordinated with the attenuated pressure differential on the orifice to minimize orifice frictional coeflicients while producing the desired fuel flow.

ARLINGTON MOORE. 

